December 20, 2023 — The following was released by NOAA Fisheries:
Sturgeon are incredibly resilient fish. Fossil records of sturgeon date back to the Cretaceous period—more than 260 million years ago. Today, there are 25 different species of sturgeon worldwide. But due to overfishing, water pollution, vessel strikes, and lack of access to habitat they need, many sturgeon species have declined. Nine species of sturgeon are listed as either threatened or endangered under the Endangered Species Act. They are considered one of the world’s most endangered groups of species.
There are five distinct population segments of Atlantic sturgeon in the United States. Four of these segments are considered endangered. The other is considered threatened.
One of the distinct population segments of this fish that is endangered is located in the Chesapeake Bay. To help the Chesapeake population rebound, NOAA is working with partners to:
- Study their abundance, reproduction, and distribution
- Identify and protect habitat they need during their life cycle
- Minimize dangers they face, including from ship strikes
- Introduce students to these fascinating fish
Telemetry Helps Track Fish Numbers, Movement
One way scientists learn more about Atlantic sturgeon is by tracking their movements using acoustic telemetry. Telemetry uses sound to relay information across open space. Scientists surgically insert special sound-emitting tags into fish. Then, receivers stationed in the water detect when those tagged fish swim near the receivers. Understanding sturgeon movement over time and space can help efforts to protect them.
“We tag sturgeon every year, and we’re trying to maintain about 100 active tags,” said Dr. Jason Kahn, NOAA Fisheries’ Office of Protected Resources, of an effort based in Virginia’s York River. “Generally that means tagging about 10 to 15 fish per year.”
The largest telemetry tags have batteries that last for about 10 years, but smaller tags may only last for a few months.
“There are two tags from 2013 that are still working. But we have retagged perhaps 10 or 12 fish when they got toward the end of one tag’s battery life, so that really extends the time we have information on individual fish,” Kahn noted.